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Persistence of detectable insecticidal proteins from #Bacillus thuringiensis# (Cry) and toxicity after adsorption on contrasting soils Full text
2016
Hung T.P. | Truong L.V. | Binh N.D. | Frutos R. | Quiquampoix H. | Staunton S.
Persistence of detectable insecticidal proteins from #Bacillus thuringiensis# (Cry) and toxicity after adsorption on contrasting soils Full text
2016
Hung T.P. | Truong L.V. | Binh N.D. | Frutos R. | Quiquampoix H. | Staunton S.
Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro, paralleled by decreasing solubilisation in the larval gut. (Résumé d'auteur)
Show more [+] Less [-]Persistence of detectable insecticidal proteins from Bacillus thuringiensis (Cry) and toxicity after adsorption on contrasting soils Full text
2016
Hung, T.P. | Truong, L.V. | Binh, N.D. | Frutos, R. | Quiquampoix, H. | Staunton, S.
Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro, paralleled by decreasing solubilisation in the larval gut.
Show more [+] Less [-]Decision support tool for soil sampling of heterogeneous pesticide (chlordecone) pollution Full text
2014
Clostre F. | Lesueur Jannoyer M. | Achard R. | Letourmy P. | Cabidoche Y.M. | Cattan P.
Decision support tool for soil sampling of heterogeneous pesticide (chlordecone) pollution Full text
2014
Clostre F. | Lesueur Jannoyer M. | Achard R. | Letourmy P. | Cabidoche Y.M. | Cattan P.
When field pollution is heterogeneous due to localized pesticide application, as is the case of chlordecone (CLD), the mean level of pollution is difficult to assess. Our objective was to design a decision support tool to optimize soil sampling. We analyzed the CLD heterogeneity of soil content at 0-30- and 30-60-cm depth. This was done within and between nine plots (0.4 to 1.8 ha) on andosol and ferralsol. We determined that 20 pooled subsamples per plot were a satisfactory compromise with respect to both cost and accuracy. Globally, CLD content was greater for andosols and the upper soil horizon (0-30 cm). Soil organic carbon cannot account for CLD intra-field variability. Cropping systems and tillage practices influence the CLD content and distribution; that is CLD pollution was higher under intensive banana cropping systems and, while upper soil horizon was more polluted than the lower one with shallow tillage (<40 cm), deeper tillage led to a homogenization and a dilution of the pollution in the soil profile. The decision tool we proposed compiles and organizes these results to better assess CLD soil pollution in terms of sampling depth, distance, and unit at field scale. It accounts for sampling objectives, farming practices (cropping system, tillage), type of soil, and topographical characteristics (slope) to design a relevant sampling plan. This decision support tool is also adaptable to other types of heterogeneous agricultural pollution at field level. (Résumé d'auteur)
Show more [+] Less [-]Decision support tool for soil sampling of heterogeneous pesticide (chlordecone) pollution Full text
2014
Clostre, Florence | Lesueur Jannoyer, Magalie | Achard, Raphaël | Letourmy, Philippe | Cabidoche, Yves-Marie | Cattan, Philippe | Fonctionnement agroécologique et performances des systèmes de cultures horticoles (UPR HORTSYS) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Pôle de Recherche Agro-Environnementale de la Martinique ; Partenaires INRAE | Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Agrosystèmes tropicaux (ASTRO) ; Institut National de la Recherche Agronomique (INRA) | Conseil Régional de la Martinique et Ministère des Outre-Mer (France)
The online version of this article (doi:10.1007/s11356-013-2095-x) contains supplementary material, which is available to authorized users. | International audience | When field pollution is heterogeneous due to localized pesticide application, as is the case of chlordecone (CLD), the mean level of pollution is difficult to assess. Our objective was to design a decision support tool to optimize soil sampling. We analyzed the CLD heterogeneity of soil content at 0-30- and 30-60-cm depth. This was done within and between nine plots (0.4 to 1.8 ha) on andosol and ferralsol. We determined that 20 pooled subsamples per plot were a satisfactory compromise with respect to both cost and accuracy. Globally, CLD content was greater for andosols and the upper soil horizon (0-30 cm). Soil organic carbon cannot account for CLD intra-field variability. Cropping systems and tillage practices influence the CLD content and distribution; that is CLD pollution was higher under intensive banana cropping systems and, while upper soil horizon was more polluted than the lower one with shallow tillage (< 40 cm), deeper tillage led to a homogenization and a dilution of the pollution in the soil profile. The decision tool we proposed compiles and organizes these results to better assess CLD soil pollution in terms of sampling depth, distance, and unit at field scale. It accounts for sampling objectives, farming practices (cropping system, tillage), type of soil, and topographical characteristics (slope) to design a relevant sampling plan. This decision support tool is also adaptable to other types of heterogeneous agricultural pollution at field level.
Show more [+] Less [-]Decision support tool for soil sampling of heterogeneous pesticide (chlordecone) pollution Full text
2014
Clostre, Florence | Lesueur Jannoyer, Magalie | Achard, Raphaël | Letourmy, Philippe | Cabidoche, Yves-Marie | Cattan, Philippe
When field pollution is heterogeneous due to localized pesticide application, as is the case of chlordecone (CLD), the mean level of pollution is difficult to assess. Our objective was to design a decision support tool to optimize soil sampling. We analyzed the CLD heterogeneity of soil content at 0–30- and 30–60-cm depth. This was done within and between nine plots (0.4 to 1.8 ha) on andosol and ferralsol. We determined that 20 pooled subsamples per plot were a satisfactory compromise with respect to both cost and accuracy. Globally, CLD content was greater for andosols and the upper soil horizon (0–30 cm). Soil organic carbon cannot account for CLD intra-field variability. Cropping systems and tillage practices influence the CLD content and distribution; that is CLD pollution was higher under intensive banana cropping systems and, while upper soil horizon was more polluted than the lower one with shallow tillage (<40 cm), deeper tillage led to a homogenization and a dilution of the pollution in the soil profile. The decision tool we proposed compiles and organizes these results to better assess CLD soil pollution in terms of sampling depth, distance, and unit at field scale. It accounts for sampling objectives, farming practices (cropping system, tillage), type of soil, and topographical characteristics (slope) to design a relevant sampling plan. This decision support tool is also adaptable to other types of heterogeneous agricultural pollution at field level.
Show more [+] Less [-]Carbonaceous aerosol at urban and rural sites in the United States.
1986
Shah J.J. | Johnson R.L. | Heyerdahl E.K. | Huntzicker J.J.
An overview of hazardous/toxic waste incineration.
1986
Lee C.C. | Huffman G.L. | Oberacker D.A.
Field evaluation of hazardous waste pretreatment as an air pollution control technique.
1986
Allen C.C. | Blaney B.L. | Brant G. | Simpson S.
The regulation of toxic air pollutants. A critical review.
1986
Cannon J.A.
Assessing impacts of ozone on agricultural crops. II. Crop yield functions and alternative exposure statistics [Barley, beans, cotton, peanuts, sorghum, soybeans, tomato, wheat].
1984
Heck W.W. | Cure W.W. | Rawlings J.O. | Zaragoza L.J. | Heagle A.S. | Heggestad H.E. | Kohut R.J. | Kress L.W. | Temple P.J.
Assessing impacts of ozone on agricultural crops. I. Overview.
1984
Heck W.W. | Cure W.W. | Rawlings J.O. | Zaragoza L.J. | Heagle A.S. | Heggestad H.E. | Kohut R.J. | Kress L.W. | Temple P.J.
A rainfall simulator for laboratory use in acidic precipitation studies.
1984
Chevone B.I. | Yang Y.S. | Winner W.E. | Storks Cotter I. | Long S.J.
An update on college and university programs in air pollution control [USA].
1983
Cota H.M.